﻿/*
* jQuery Plugin: Tokenizing Autocomplete Text Entry
* Version 1.1
*
* Copyright (c) 2009 James Smith (http://loopj.com)
* Licensed jointly under the GPL and MIT licenses,
* choose which one suits your project best!
*
*/

(function ($) {

    $.fn.tokenInput = function (url, options) {
        var settings = $.extend({
            url: url,
            hintText: "Type in a search term",
            noResultsText: "No results",
            searchingText: "Searching...",
            searchDelay: 300,
            minChars: 1,
            tokenLimit: -1,
            jsonContainer: null,
            method: "GET",
            contentType: "json",
            queryParam: "q",
            onResult: null,
            allowRemove: true
        }, options);
        $.fn.tokenInput.url = url;
        settings.classes = $.extend({
            tokenList: "token-input-list",
            token: "token-input-token",
            tokenDelete: "token-input-delete-token",
            selectedToken: "token-input-selected-token",
            highlightedToken: "token-input-highlighted-token",
            dropdown: "token-input-dropdown",
            dropdownItem: "token-input-dropdown-item",
            dropdownItem2: "token-input-dropdown-item2",
            selectedDropdownItem: "token-input-selected-dropdown-item",
            inputToken: "token-input-input-token"
        }, options.classes);

        return this.each(function () {
            var list = new $.TokenList(this, settings);
        });
    };
    $.fn.tokenInput.url = null;
    $.TokenList = function (input, settings) {
        //
        // Variables
        //

        // Input box position "enum"
        var POSITION = {
            BEFORE: 0,
            AFTER: 1,
            END: 2
        };

        // Keys "enum"
        var KEY = {
            BACKSPACE: 8,
            TAB: 9,
            RETURN: 13,
            ESC: 27,
            LEFT: 37,
            UP: 38,
            RIGHT: 39,
            DOWN: 40,
            COMMA: 188
        };

        // Save the tokens
        var saved_tokens = [];

        // Keep track of the number of tokens in the list
        var token_count = 0;

        // Basic cache to save on db hits
        var cache = new $.TokenList.Cache();

        // Keep track of the timeout
        var timeout;

        // Create a new text input an attach keyup events
        var input_box = $("<input type=\"text\">")
        .css({
            outline: "none"
        })
        .focus(function () {
            if (settings.tokenLimit == null || settings.tokenLimit != token_count) {
                show_dropdown_hint();
            }
        })
        .blur(function () {
            hide_dropdown();
        })
        .keydown(function (event) {
            var previous_token;
            var next_token;

            switch (event.keyCode) {
                case KEY.LEFT:
                case KEY.RIGHT:
                case KEY.UP:
                case KEY.DOWN:
                    if (!$(this).val()) {
                        previous_token = input_token.prev();
                        next_token = input_token.next();

                        if ((previous_token.length && previous_token.get(0) === selected_token) || (next_token.length && next_token.get(0) === selected_token)) {
                            // Check if there is a previous/next token and it is selected
                            if (event.keyCode == KEY.LEFT || event.keyCode == KEY.UP) {
                                deselect_token($(selected_token), POSITION.BEFORE);
                            } else {
                                deselect_token($(selected_token), POSITION.AFTER);
                            }
                        } else if ((event.keyCode == KEY.LEFT || event.keyCode == KEY.UP) && previous_token.length) {
                            // We are moving left, select the previous token if it exists
                            select_token($(previous_token.get(0)));
                        } else if ((event.keyCode == KEY.RIGHT || event.keyCode == KEY.DOWN) && next_token.length) {
                            // We are moving right, select the next token if it exists
                            select_token($(next_token.get(0)));
                        }
                    } else {
                        var dropdown_item = null;

                        if (event.keyCode == KEY.DOWN || event.keyCode == KEY.RIGHT) {
                            dropdown_item = $(selected_dropdown_item).next();
                        } else {
                            dropdown_item = $(selected_dropdown_item).prev();
                        }

                        if (dropdown_item.length) {
                            select_dropdown_item(dropdown_item);
                        }
                        return false;
                    }
                    break;

                case KEY.BACKSPACE:
                    previous_token = input_token.prev();

                    if (!$(this).val().length) {
                        if (selected_token) {
                            delete_token($(selected_token));
                        } else if (previous_token.length) {
                            select_token($(previous_token.get(0)));
                        }

                        return false;
                    } else if ($(this).val().length == 1) {
                        hide_dropdown();
                    } else {
                        // set a timeout just long enough to let this function finish.
                        setTimeout(function () { do_search(false); }, 5);
                    }
                    break;

                case KEY.TAB:
                case KEY.RETURN:
                case KEY.COMMA:
                    if (selected_dropdown_item) {
                        add_token($(selected_dropdown_item));
                        return false;
                    }
                    break;

                case KEY.ESC:
                    hide_dropdown();
                    return true;

                default:
                    if (is_printable_character(event.keyCode)) {
                        // set a timeout just long enough to let this function finish.
                        setTimeout(function () { do_search(false); }, 5);
                    }
                    break;
            }
        });

        // Keep a reference to the original input box
        var hidden_input = $(input)
                           .hide()
                           .focus(function () {
                               input_box.focus();
                           })
                           .blur(function () {
                               input_box.blur();
                           });

        // Keep a reference to the selected token and dropdown item
        var selected_token = null;
        var selected_dropdown_item = null;

        // The list to store the token items in
        var token_list = $("<ul />")
        .addClass(settings.classes.tokenList)
        .insertAfter(hidden_input)
        .click(function (event) {

            var li = get_element_from_event(event, "li");

            if (li && li.get(0) != input_token.get(0)) {
                toggle_select_token(li);
                return false;
            } else {
                input_box.focus();

                if (selected_token) {
                    deselect_token($(selected_token), POSITION.END);
                }
            }
        })
        .mouseover(function (event) {
            var li = get_element_from_event(event, "li");
            if (li && selected_token !== this) {
                li.addClass(settings.classes.highlightedToken);
            }
        })
        .mouseout(function (event) {
            var li = get_element_from_event(event, "li");
            if (li && selected_token !== this) {
                li.removeClass(settings.classes.highlightedToken);
            }
        })
        .mousedown(function (event) {
            // Stop user selecting text on tokens
            var li = get_element_from_event(event, "li");
            if (li) {
                return false;
            }
        });


        // The list to store the dropdown items in
        var dropdown = $("<div>")
        .addClass(settings.classes.dropdown)
        .insertAfter(token_list)
        .hide();

        // The token holding the input box
        var input_token = $("<li />")
        .addClass(settings.classes.inputToken)
        .appendTo(token_list)
        .append(input_box);

        init_list();

        //
        // Functions
        //


        // Pre-populate list if items exist
        function init_list() {
            li_data = settings.prePopulate;
            if (li_data && li_data.length) {
                for (var i in li_data) {
                    var this_token = $("<li><p>" + li_data[i].name + "</p> </li>")
                    .addClass(settings.classes.token)
                    .addClass('astype' + li_data[i].type)
                    .insertBefore(input_token);

                    if (settings.allowRemove) {
                        $("<span>x</span>")
                    .addClass(settings.classes.tokenDelete)
                    .appendTo(this_token)
                    .click(function () {
                        delete_token($(this).parent());
                        return false;
                    });
                    };
                    $.data(this_token.get(0), "tokeninput", { "id": li_data[i].id, "name": li_data[i].name, "type": li_data[i].type });

                    // Clear input box and make sure it keeps focus
                    input_box
                    .val("")
                    .focus();

                    // Don't show the help dropdown, they've got the idea
                    hide_dropdown();

                    // Save this token id
                    var id_string = li_data[i].id + ':' + li_data[i].type + ","
                    hidden_input.val(hidden_input.val() + id_string);
                    token_count++;

                    if (settings.tokenLimit != null && settings.tokenLimit >= token_count) {
                        input_box.hide();
                        hide_dropdown();
                    }
                }
            }
        }

        function is_printable_character(keycode) {
            if ((keycode >= 48 && keycode <= 90) ||      // 0-1a-z
           (keycode >= 96 && keycode <= 111) ||     // numpad 0-9 + - / * .
           (keycode >= 186 && keycode <= 192) ||    // ; = , - . / ^
           (keycode >= 219 && keycode <= 222)       // ( \ ) '
          ) {
                return true;
            } else {
                return false;
            }
        }

        // Get an element of a particular type from an event (click/mouseover etc)
        function get_element_from_event(event, element_type) {
            var target = $(event.target);
            var element = null;

            if (target.is(element_type)) {
                element = target;
            } else if (target.parent(element_type).length) {
                element = target.parent(element_type + ":first");
            }

            return element;
        }

        // Inner function to a token to the list
        function insert_token(id, value, type) {
            var this_token = $("<li><p>" + value + "</p> </li>")
      .addClass(settings.classes.token)
      .addClass('astype' + type)
      .insertBefore(input_token);

            // The 'delete token' button
            if (settings.allowRemove) {
                $("<span>x</span>")
          .addClass(settings.classes.tokenDelete)
          .appendTo(this_token)
          .click(function () {
              delete_token($(this).parent());
              return false;
          });
            };

            $.data(this_token.get(0), "tokeninput", { "id": id, "name": value, "type": type });

            return this_token;
        }

        // Add a token to the token list based on user input
        function add_token(item) {
            var li_data = $.data(item.get(0), "tokeninput");
            var this_token = insert_token(li_data.id, li_data.name, li_data.type);

            // Clear input box and make sure it keeps focus
            input_box
            .val("")
            .focus();

            // Don't show the help dropdown, they've got the idea
            hide_dropdown();

            // Save this token id
            var id_string = li_data.id + ':' + li_data.type + ","
            hidden_input.val(hidden_input.val() + id_string);

            token_count++;

            if (settings.tokenLimit != null && token_count>=settings.tokenLimit) {
                input_box.hide();
                hide_dropdown();
            }
        }

        // Select a token in the token list
        function select_token(token) {
            token.addClass(settings.classes.selectedToken);
            selected_token = token.get(0);

            // Hide input box
            input_box.val("");

            // Hide dropdown if it is visible (eg if we clicked to select token)
            hide_dropdown();
        }

        // Deselect a token in the token list
        function deselect_token(token, position) {
            token.removeClass(settings.classes.selectedToken);
            selected_token = null;

            if (position == POSITION.BEFORE) {
                input_token.insertBefore(token);
            } else if (position == POSITION.AFTER) {
                input_token.insertAfter(token);
            } else {
                input_token.appendTo(token_list);
            }

            // Show the input box and give it focus again
            input_box.focus();
        }

        // Toggle selection of a token in the token list
        function toggle_select_token(token) {
            if (selected_token == token.get(0)) {
                deselect_token(token, POSITION.END);
            } else {
                if (selected_token) {
                    deselect_token($(selected_token), POSITION.END);
                }
                select_token(token);
            }
        }

        // Delete a token from the token list
        function delete_token(token) {
            // Remove the id from the saved list
            var token_data = $.data(token.get(0), "tokeninput");

            // Delete the token
            token.remove();
            selected_token = null;

            // Show the input box and give it focus again
            input_box.focus();

            // Delete this token's id from hidden input
            var str = hidden_input.val()
            var start = str.indexOf(token_data.id + ':' + token_data.type + ",");
            var end = str.indexOf(",", start) + 1;

            if (end >= str.length) {
                hidden_input.val(str.slice(0, start));
            } else {
                hidden_input.val(str.slice(0, start) + str.slice(end, str.length));
            }

            token_count--;

            if (settings.tokenLimit != null) {
                input_box
                .show()
                .val("")
                .focus();
            }
        }

        // Hide and clear the results dropdown
        function hide_dropdown() {
            dropdown.hide().empty();
            selected_dropdown_item = null;
        }

        function show_dropdown_searching() {
            dropdown
            .html("<p>" + settings.searchingText + "</p>")
            .show();
        }

        function show_dropdown_hint() {
            dropdown
            .html("<p>" + settings.hintText + "</p>")
            .show();
        }

        // Highlight the query part of the search term
        function highlight_term(value, term) {
            return value.replace(new RegExp("(?![^&;]+;)(?!<[^<>]*)(" + term + ")(?![^<>]*>)(?![^&;]+;)", "gi"), "<b>$1</b>");
        }

        // Populate the results dropdown with some results
        function populate_dropdown(query, results) {
           
            if (results.length) {
                dropdown.empty();

                var dropdown_ul = $("<ul>")
                .appendTo(dropdown)
                .mouseover(function (event) {
                    select_dropdown_item(get_element_from_event(event, "li"));
                })
                .mousedown(function (event) {
                    add_token(get_element_from_event(event, "li"));
                    return false;
                })
                .hide();

                for (var i in results) {
                    if (results.hasOwnProperty(i)) {
                        var this_li = $("<li>" + highlight_term(results[i].name, query) + "</li>").appendTo(dropdown_ul);
                        if (i % 2) {
                            this_li.addClass(settings.classes.dropdownItem);
                        } else {
                            this_li.addClass(settings.classes.dropdownItem2);
                        }
                        this_li.addClass('astype' + results[i].type);

                        if (i == 0) {
                            select_dropdown_item(this_li);
                        }

                        $.data(this_li.get(0), "tokeninput", { "id": results[i].id, "name": results[i].name, "type": results[i].type });
                    }
                }

                dropdown.show();
                dropdown_ul.slideDown("fast");

            } else {
                dropdown
                .html("<p>" + settings.noResultsText + "</p>")
                .show();
            }
        }

        // Highlight an item in the results dropdown
        function select_dropdown_item(item) {
            if (item) {
                if (selected_dropdown_item) {
                    deselect_dropdown_item($(selected_dropdown_item));
                }

                item.addClass(settings.classes.selectedDropdownItem);
                selected_dropdown_item = item.get(0);
            }
        }

        // Remove highlighting from an item in the results dropdown
        function deselect_dropdown_item(item) {
            item.removeClass(settings.classes.selectedDropdownItem);
            selected_dropdown_item = null;
        }

        // Do a search and show the "searching" dropdown if the input is longer
        // than settings.minChars
        function do_search(immediate) {
            var query = input_box.val().toLowerCase();

            if (query && query.length) {
                if (selected_token) {
                    deselect_token($(selected_token), POSITION.AFTER);
                }
                if (query.length >= settings.minChars) {
                    show_dropdown_searching();
                    if (immediate) {
                        run_search(query);
                    } else {
                        clearTimeout(timeout);
                        timeout = setTimeout(function () { run_search(query); }, settings.searchDelay);
                    }
                } else {
                    hide_dropdown();
                }
            }
        }

        // Do the actual search
        function run_search(query) {
            var cached_results = cache.get(query);
            if (cached_results) {
                populate_dropdown(query, cached_results);
            } else {
                var queryStringDelimiter = settings.url.indexOf("?") < 0 ? "?" : "&";
                var callback = function (results) {
                    if ($.isFunction(settings.onResult)) {
                        results = settings.onResult.call(this, results);
                    }
                    cache.add(query, settings.jsonContainer ? results[settings.jsonContainer] : results);
                    populate_dropdown(query, settings.jsonContainer ? results[settings.jsonContainer] : results);
                };
                //var url = $.fn.tokenInput.url;
                var url = settings.url;
                if (settings.method == "POST") {
                    $.post(url + queryStringDelimiter + settings.queryParam + "=" + query, {}, callback, settings.contentType);
                } else {
                    $.get(url + queryStringDelimiter + settings.queryParam + "=" + query, {}, callback, settings.contentType);
                }
            }
        }
    };

    // Really basic cache for the results
    $.TokenList.Cache = function (options) {
        var settings = $.extend({
            max_size: 50
        }, options);

        var data = {};
        var size = 0;

        var flush = function () {
            data = {};
            size = 0;
        };

        this.add = function (query, results) {
            if (size > settings.max_size) {
                flush();
            }

            if (!data[query]) {
                size++;
            }

            data[query] = results;
        };

        this.get = function (query) {
            return data[query];
        };
    };


})(jQuery);